I would like to know the best method monitoring a large number of switches and routers on a network for reachability via ICMP. Currently we have systems in place to monitor via SNMP traps however this is not always reliable and can be slow sometimes.

I am worried about setting up a perl script to ping 500+ routers/switches concurrently to test for reachability because I am worried about the PC load doing this ? or is this not going to use alot of resources ? I would like a script that can accept in a text file a list of all hostnames/IP to be scanned and the perl script to do the scanning of the large number of hosst fro the host file.

I would then like a seperate text file that the results will be sent to showing the same list of hosts in the hosts text file but putting a 0 next to the device if it is not reachable and 1 if it is reachable via ICMP ping.